C43.111
BillableMalignant melanoma of right upper eyelid, including canthus
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is C43.111 an HCC code?
Yes. C43.111 maps to Melanoma and Other Skin Cancers under the CMS-HCC V28 risk adjustment model (and Breast, Prostate, and Other Cancers and Tumors under V24).
HCC Category Mapping
RAF weights shown are the community, non-dual, aged base weights from the CMS risk adjustment model file. Actual per-patient RAF contribution depends on member segment, interactions, and the model year used by the payer. V28 is the CMS-HCC model phased in over payment years 2024–2026; V24 remains in use during the transition and for historical data.
MEAT Criteria for C43.111
For C43.111 to count as a valid HCC diagnosis in a given encounter, the provider's documentation must show MEAT: Monitor, Evaluate, Assess, or Treat. A diagnosis from a prior year does not carry forward automatically — it has to be re-documented and supported each calendar year.
- MMonitor: signs, symptoms, disease progression, or lab trending documented in the note
- EEvaluate: test results, medication response, or physical findings reviewed by the provider
- AAssess: explicit mention in the assessment or plan with acknowledgment of status
- TTreat: medication, referral, procedure, therapy, or counseling tied to the diagnosis
Only one of M/E/A/T is required to support the code, but the documentation must be specific enough to show that the provider actually addressed C43.111 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
C43.111 is the ICD-10-CM diagnosis code for malignant melanoma of right upper eyelid, including canthus. Melanoma of the upper eyelid of the right eye, including the corner of the eye (canthus). C43.111 sits in the ICD-10-CM chapter for neoplasms (c00-d49), within the section covering melanoma and other malignant neoplasms of skin (c43-c44).
Under the CMS-HCC V28 risk adjustment model, C43.111 maps to Melanoma and Other Skin Cancers (HCC 23) with a community, non-dual, aged base RAF weight of 0.251. Under the older CMS-HCC V24 model, C43.111 maps to Breast, Prostate, and Other Cancers and Tumors (HCC 12) with a community, non-dual, aged base RAF weight of 0.150. V28 is the CMS-HCC risk adjustment model that reached 100% phase-in for payment year 2026, replacing V24 which was used during the PY2024–PY2025 transition.
The fifth digit '1' specifies right upper eyelid; ensure documentation confirms this specific location. Because C43.111 maps to a payment HCC, the provider's documentation must satisfy MEAT criteria (Monitor, Evaluate, Assess, or Treat) for the encounter to count toward the patient's Medicare Advantage risk adjustment score. When documentation is ambiguous, coders should issue a provider query rather than assume the highest-specificity variant.
HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for C43.111 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •The fifth digit '1' specifies right upper eyelid; ensure documentation confirms this specific location
- •Canthus refers to the corner where upper and lower eyelids meet; document if involved
Clinical Significance
Malignant melanoma of the right upper eyelid, including the canthus. This is the most specific code for this location and laterality. Upper eyelid melanomas have distinct surgical considerations because of proximity to the brow and lacrimal apparatus. Wide excision with reconstruction and sentinel lymph node biopsy of parotid and cervical basins are typical.
Documentation Requirements
- ✓Right side and upper eyelid explicitly documented
- ✓Breslow depth (millimeters of invasion)
- ✓Ulceration status
- ✓Whether the medial or lateral canthus is involved
- ✓Sentinel lymph node biopsy results
- ✓AJCC staging and mitotic rate